[DragonFlyBSD - Bug #2863] HAMMER synch tid is zero

bugtracker-admin at leaf.dragonflybsd.org bugtracker-admin at leaf.dragonflybsd.org
Thu Dec 10 08:27:49 PST 2015


Issue #2863 has been updated by shamaz.


OK. This is my test case (posted it on pastebin). Just please try to reproduce it to see if it's the same on recent version or master.

http://pastebin.com/Ag36fDxT

If you do not see anything unusual: see carefully on snapshot timestamps and TIDs. Snapshot with transaction ID 0x0000000000000000 is not the earliest. Looks to me, you initialize your "internal flusher data structure" too late, maybe on the first write or something like that. Maybe this is not critical and can be ignored, you decide.

----------------------------------------
Bug #2863: HAMMER synch tid is zero
http://bugs.dragonflybsd.org/issues/2863#change-12769

* Author: shamaz
* Status: New
* Priority: Normal
* Assignee: 
* Category: 
* Target version: 
----------------------------------------
Hello. This appears on DragonFlyBSD 4.2 (and maybe newer) if you try the
following with HAMMER filesystem:

1) Create a new vnode device.
# dd if=/dev/zero of=test.img bs=1m count=15000
# vnconfig -c vn test.img
# disklabel64  -w -r vn4s0 auto
# disklabel64 -e vn4s0
Add a line like "a:      *      0     HAMMER"

2) Create a HAMMER filesystem:
newfs_hammer -f -L TEST /dev/vn4s0a

3) Mount it:
mount /dev/vn4s0a /mnt

4) Try to sync it:
hammer synctid /mnt

You will see zero sync tid (0x0000000000000000). If you try to set some
debug-related sysctls, it will get you no info at all when syncing. Also
hammer pfs-status /mnt will show that sync-end-tid does not increment in
time as it should. I am not sure if it happens with any non-root hammer FS,
or just with those based on vn pseudo disks.



-- 
You have received this notification because you have either subscribed to it, or are involved in it.
To change your notification preferences, please click here: http://bugs.dragonflybsd.org/my/account



More information about the Bugs mailing list